Securities - Narrative (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2023 USD ($) security	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) security	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($) security
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
AFS and HTM, accrued interest | $	$ 41,000,000		$ 41,000,000		$ 41,800,000
Number of available-for-sale debt securities in an unrealized loss position | security	564		564		559
Debt Securities, AFS, allowance for credit loss | $	$ 0		$ 0		$ 0
Provision (reversal of provision) for credit losses | $	0	$ 0	0	$ 0
HTM securities allowance for credit loss | $	0		0		0
Asset Pledged as Collateral
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
AFS and HTM debt securities carrying value | $	$ 7,210,000,000		$ 7,210,000,000		$ 794,200,000
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Number of available-for-sale debt securities in an unrealized loss position | security	269		269		263
Non-agency mortgage-backed securities
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Number of available-for-sale debt securities in an unrealized loss position | security	99		99		100
Corporate debt securities
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Number of available-for-sale debt securities in an unrealized loss position | security	66		66		68
U.S. Treasury securities
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Number of available-for-sale debt securities in an unrealized loss position | security	15		15		15